1. Field of the Invention
This invention relates to a compressible pad for supporting a wood floor, such as, but not restricted to, a hardwood sports floor above a base.
2. Background Information
For many indoor athletic venues, particularly venues where basketball is a major sport, hardwood floors remain the playing surface of choice. Hardwood floors provide uniform performance characteristics over a relatively long period of time. Hardwood floors are esthetically pleasing, and properly designed and installed hardwood floors help to minimize wear and tear on the bodies of the athletes performing on the surface of such floors.
Typically, to minimize wear and tear, hardwood sports floors provide some amount of vertical “give”, or deflection, which results from the use of resilient pads which support the floor above a base. In many cases the pads are arranged in parallel rows along the bottom surfaces of a sub-floor structure, and floorboards are secured to the top of the sub-floor. A typical resilient hardwood floor system of this type has been sold for a number of years, under the trademark PERMACUSHION. These resilient pads are used within a flooring system to provide cushioning and vibration control.
With this type of floor, because the sub-floor and the upper floorboards are supported in spaced relation above the base via the pads, there exists a certain amount of vertical clearance space between the under side of the sub-floor and the base, thereby allowing air circulation. This helps to minimize potential problems which may otherwise be caused by the intake or egress of moisture by the wooden floor components, either due to flooding or moisture resulting from humidity in the air.
The particular composition and structure of the pads helps to determine the overall vertical deflectability, or resiliency of the floor structure located above. That is, to provide the desired vertical deflection, prior hardwood floor pads have come in a number of different shapes and sizes. Often the pads include void spaces to accommodate some desired amount of deflection, with the void spaces opening either in the vertical direction or in the horizontal direction.
But, for many athletic venues, particularly in venues where the cost constraints may be greatest, the preferred hardwood floor may be a relatively simple structure of the type described above, with an upper layer of floorboards supported on a sub-floor, most likely parallel spaced rows of attachment members laid end to end, and supported above a base by a plurality of uniformly distributed pads. For these floors the pads must provide a desired amount of vertical spacing above the base and vertical deflectability for the upper floor surface when the floor is in use. Also, because the weight of the sub-floor and the floorboards supplies some amount of initial compression to the pads, i.e. when in a “static loaded” condition, the design, the shape and composition of the pads must take into account the degree of compression of the pad in the static loaded condition, and the further compressibility of the pad which is available when the pads are “loaded” due to additional force or weight applied to the floor above.
One commonly used pad for floors of this type includes spaced upper and lower pieces held apart by a plurality of parallel rows of vertical supports defining a plurality of parallel rows of rectangular-shaped horizontal passages between the upper and lower pieces. The rectangular-shaped passages within the pads provide some amount of void space to facilitate compression of the pads, to a degree determined by the material of the pad, the amount of loading to the floor, and the density and/or distribution of the pads used to support the floor. Typically, these pads are integrally molded, as by extrusion. This particular pad has proven well suitable for extended time in supporting hardwood floors in many athletic venues.
Nevertheless, as a result of testing the compressibility of these pads, particularly the restoring forces of these pads, i.e., the ability of the pad to reassume its original state, i.e. to decompress, to the static loaded condition, can be improved. For instance, with these pads, it has been experienced that in some cases the parallel longitudinal supports may buckle sideways after being subjected to excessive vertical loads, or loads over a long period of time. Moreover, because the upper layer of floorboards may expand and contract due to moisture intake and egress, as a result of humidity changes, and because the pads usually frictionally engage the base, even in a static state the pads may be subjected to and required to withstand some horizontal sheer forces. These sheer forces may promote, or accelerate, the undesired buckling of the supports. Once buckling occurs, the pads can eventually become transformed into incompressible masses.
This can significantly reduce the resiliency of the floor, or even make the resiliency negligible.
Traditional molded and extruded pads commit to a shape and then tailor their performance through manipulating material properties. These different pads, with different performance levels are traditionally identified through different color materials. The lack of geometric differences requires that the pads be different colors as one can not visually distinguish the difference between a hard and a soft pad.
One can not easily, quickly, or cheaply change the geometry, even slightly, of a molded or an extruded pad to tweak performance.
As will be seen from the subsequent description of the preferred embodiments of the present invention overcomes these and other shortcoming of existing floor pads in an economic and efficient manner.